Here’s an oldie but goodie — the IMSAI 8080, a 1975 clone of the pioneering Altair 8800. Like the Altair, it used an S-100 bus, an Intel 8080 CPU, and a blue, boxy sheet metal case with front panel lights. Unlike the Altair, the IMSAI 8080 featured prominently in the 1983 movie WarGames. The machine apparently greatlyannoyed Ed Roberts, the inventor of the Altair.

[ From BYTE, February 1977, p.48 ]

Discussion Topic: Have you ever used an IMSAI 8080 or Altair 8800? Tell us about it.

8 Responses to “[ Retro Scan ] IMSAI 8080”

Although these were from before my time. I came across a Altair 8800 that had been decked out to the hilt back in 1993 at a goodwill in Oregon. I bought it for $15.00 including a nice pair of 8 inch floppy drives, a no name keyboard, and a 9 inch monochrome monitor.
When I got it all home and set it up, It powered up and ran to a command prompt on the screen, but I was never able to find any disks for it, and as it had no basic interpreter or for that matter any operating system at all, I could do nothing with it. If I had only known its worth or that this thing called the internet would come to be, I would have hung onto it.
Sadly it and about a dozen other vintage systems went to the trash when I moved back to the east coast.

Not sure about this machine, but the similar Altair 8800 came with a BASIC interpreter and could run CP/M (with an expansion board), so either whatever one could program (or type in from a source listing) or whatever software existed for CP/M at the time. Can’t imagine there was much.

I had a chance to play with the IMSAI back in the early 1980s when one of my college friends put a system together. Once you bought memory boards and a disk controller card and a couple of disk drives the price escalated pretty quickly. You also needed a terminal, or (preferably) a video card and keyboard. But it made a heck of a CP/M development system. And one of the best C compilers ever written for 8 bit machines was written using the IMSAI 8080. Leor Zolman was an MIT student who started a company called Brain Damage Software and developed BDS C, the first reasonably priced C compiler for CP/M systems. Leor is one of the unrecognized pioneers of the microcomputer revolution, and his first computer was the IMSAI 8080.

Wow. A little before my time (I didn’t use my first computer until about ’83â€”the TRS-80), but it’s still amazing to see the very beginnings of the PC industry. Man what a price tag tooâ€”almost $1000 assembled? It would be one thing to know how to program, but to have that kind of cash back then?